Cystic fibrosis (CF) is a recessive, single gene disease affecting about 1/2000 Caucasians-, exocrine secretion is affected, and the most serious consequence is a compromise of mucosal defenses in the lung, leading to chronic respiratory infections. Median survival age is about 23 years. The CF gene codes for a 1480 amino acid putative membrane protein (CFTR) with 2 nucleotide binding domains. The two defective alleles identified so far are a single amino acid deletion (68%) or substitution (4%) in the N-terminal nucleotide binding domain. The most throughly described cellular abnormality in CF is a marked reduction of chloride permeability in several cells types, leading to hyposecretion of fluid and altered salt and water reabsorption. The general goal of this proposal is to enable the visiting researcher to gain direct experience with a set of methods not currently available in his laboratory while attempting to answer important questions about the molecular basis of the transport defect in CF. Specific research goals include mapping the cellular and subcellular distribution of the CFTR as a prelude to expression studies. Proposed studies require the visiting researcher to learn RNA preparation, Northern and Western blotting, PCR techniques, immunoprecipitation, and immunohistochemistry, production of polyclonal and monoclonal antibodies, immunogold labeling, analysis of electromicrographs, and possibly pulse labeling techniques.